[PATCH v3 0/4] Bug fixes for Qualcomm BT chip wcn3990

From: Balakrishna Godavarthi
Date: Fri Nov 30 2018 - 10:03:13 EST


The below issues are found in the recent testing.

1. Observed device is not going into off state or not responding.
As wcn3990 require a power pulses to turn on the irrespctive of
igniting regulators, it was observed that power on or power off
pulses are not in sync with respective to chip.
The below patch will help us to wait until byte is pushed on to wires.

* Bluetooth: hci_qca: use wait_until_sent() for power pulses

2. Observed Chip responding when we are in sleep.
This is due to turn on flow control during change baudrate request.
The below patch will only pull the RTS line high instead of turning off
the flow.

* Bluetooth: hci_qca: Pull RTS line high for baudrate change command.

3. Frame reassembly errors splashing on console.
wcn3990 requires will use multiple baudrates during booting stage.
i.e. 2400 bps while sending power off pulse
115200 bps while sending power on pulse
port close
port open
set baudrate to 115200 request the chip version.

during above process, we are seeing some stray bytes coming up
on the UART Rx FIFO it could be due to frequent baudrate change.

This patch will stop the frame reassembly errors.

* Bluetooth: hci_qca: Fix frame reassembly errors for wcn3990

4. Disable IBS state machine and flush Tx buffer
We are disabling IBS and flushing the Tx buffer before turning off the chip.

This is due to IBS state machine is active when we turn off the chip.
This will stop queuing IBS protocol bytes.

* Bluetooth: hci_qca: Disable IBS state machine and flush Tx buffer

Changes in v3:
* moved IBS & qca_flush to different patch
* updated comments in code fo Deassert RTS patch

Changes in v2:
* Removed Bluetooth: hci_qca: clear HCI_QUIRK_RESET_ON_CLOSE flag patch
will be sending as separate series.
Balakrishna Godavarthi (4):
Bluetooth: hci_qca: use wait_until_sent() for power pulses
Bluetooth: hci_qca: Deassert RTS while baudrate change command
Bluetooth: hci_qca: Fix frame reassembly errors for wcn3990
Bluetooth: hci_qca: Disable IBS state machine and flush Tx buffer

drivers/bluetooth/hci_qca.c | 77 +++++++++++++++++++++----------------
1 file changed, 43 insertions(+), 34 deletions(-)

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